The present invention relates to irrigation systems and pertains particularly to a pressure compensating flow control valve for emitters and the like.
Due to the scarcity of water for irrigation purposes in many countries of the world, drip and trickle irrigation systems are becoming widely used. Spray systems are also widely used in many areas and conserve a considerable amount of water over the old fashioned flooding system predominant in many areas.
Drip, trickle and sprinkler systems normally employ a series of conduits carrying water to emitters placed along the length of the conduits for dispensing water at a controlled rate. It is desirable that the system has equal water pressure and flow at each of the emitters. Since it is difficult to obtain equal pressure throughout the system, the system must have some means for compensating for the variations in pressure to achieve a substantially constant flow output from each emitter whether the emitter is spray, drip, or trickle type.
Many systems have been proposed for controlling water flow from emitters. Such systems have met varying degrees of success and have various drawbacks. Some of the more successful systems from the point of functioning and reliability are extremely complicated and expensive and are therefor not feasible for many installations.
It is therefore desirable that some simple, inexpensive and effective flow control means be available for controlling the flow of water in an irrigation system.